MMU descriptor having big/little endian bit to control the transfer data between devices

摘要

A digital system is provided with a memory (506) shared by several initiator resources (540-550), wherein a portion of the initiator resources are big endian and another portion of the initiator resources are little endian. The memory is segregated into a set of regions by a memory management unit (MMU) (500-510) and an endianism attribute bit is defined for each region. For each memory request to the memory, the endianism attribute bit for the selected region is provided by the MMU. Each memory transaction request is completed in accordance with the endianism attribute of the selected region. Depending on the capability of a given initiator resource, the memory request address is adjusted to agree with the endianism attribute of the selected region, or an access fault is generated (530) if the endianism of the initiating resource does not match the endianism attribute of the selected memory region. A resource identification value (R-ID) provided by each of the initiator resources is used to identify the endianism of each of the initiator resources.